Hekhy boot



(No Model.)

H. R 0 0T.

CABLE RAILROAD.

No. 247,781. P ented 0%. 4,1881.

Mia-66020 a Von. D. c

u. Puma mmmuum i llu. Washing UNITED STATES PATENT OFFICE.

HENRY ROOT, OF SAN FRANCISCO, CALIFORNIA.

CABLE-RAILROAD.

SPECIFICATION forming part of Letters Patent No. 247,781, dated October 4, 1881.

Application filed May 6, 1881.

To all whom it may concern:

Be it known that I, HENRY R001, of the city and countyof San Francisco, State of California, have invented an Improvement in the Construction of Cable-Railways; and I hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to a cable-railway, and more especially to a peculiar construction thereof, whereby it will be possible to construct a larger tunnel or tube, and thus prevent obstruction by the accumulation of foreign matter, and whereby ready access can be had to keep it clear and in good order.

My invention consists in certain details of construction, as hereinafter described and cifically claimed.

Referring to the accompanying drawings, Figure 1 is a perspective view of my supplementary tunnel and parts above. Fig. 2 is a transverse view of the same. Fig. 3 is a longitudinal view of the same.

Let A A represent the tracks; B, the slot irons; I),tl.l6SlOlltllIUllgl] which the gripe passes. G O are the various simporting-standards, and D the cross-braces. E represents the pulleys, and G the cable passing over said pulleys. These parts constitute the mechanism of a cable-road. The practice at present is to dig a tunnel which is properly built up or in which a bent rib is placed.

In constructing tunnels for the reception of the running and supporting parts of a cableroad the object to be accomplished is to make the tunnel strong enough to resist the pressure of the earth, and'thus to keep the gripeslot uniform, for if the tunnel be weak there will be some spring to the gripe-slot, and it will cramp the gripe. For the purposes of strength, therefore,the tunnel is made as small as possible. If the bent rib, which is placed within the tunnel to receive the mechanism, were made large or deep, it would be too weak. It is therefore made just large enough to receive the running and supporting parts, and its floor or base just under the pulleys. There speis no room in the tunnel for anything but the runni'nggear, and it is so small that a limited amount of snow would soon fill it sufficiently to obstruct the mechanism.

If the tunnel now in use were made deeper, it would so weaken it that the pressure of the (No model.)

earth would have a tendency to close the gripeslot. Consequently to accomplish the object of obtaining a larger tunnel and still retain strength to keep the gripe-slot uniform, I form below the upper or ordinary tunnel containing the parts a supplementary tunnel, H, of sufficient depth to admit a workman easily. This tunnel is walled up, as shown. The upper tunnel is properly filled in to sustain the pavement above. The cross-supports D are embedded into the walls of the tunnel H toward the top, and thus form a support for the walls near the top, giving strength to the tunnels, and preventing the slotfrom closing up.

By this construction I am enabled to make the deep tunnel H, because the supports D remain near the slot-irons, and the supportingparts are not weakened. This leaves the upper part strong and well braced and the lower part free. I'thus obtain a deep tunnel while retaining the strength of a small one, because the walls of the tunnel are braced near the top. The device therefore consists of the usual tunnel, containing the working parts, and a. supplementary tunnel, to receive whatever substance may fall through the gripe-slot, and to allow easy access to the mechanism. The lower tunnel is deep enough to contain any amount of snow or other foreign substance likely to fall in, and not allow itto obstruct therunning parts above.

Appropriate man-holes will be provided in suitable places to gain access to the supple- 'mentary tunnel H. I

hand.

HENRY ROOT. Witnesses:

S. H. NOURSE, FRANK A. BROOKS. 

